• 제목/요약/키워드: Laboratory attachment

검색결과 113건 처리시간 0.031초

현장실험을 통한 건식경량벽체의 부착물에 대한 하중 저항성 평가에 관한 연구 (A Study on the Evaluation of The Load Resistancy of Lightweight Wall against Wall Attachments through Field Tests)

  • 김태익;이주민;김상헌;최수경;서치호
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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    • pp.183-184
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    • 2015
  • Recent structural approach of the House of Commons has been an increase in demand for dry wall light due to a change in load bearing composite structure of a flat plate type structure under the name of long-life housing, attach the attachment to the wall as the needs of the residents of reserved space increases things that are on the rise. However, depending on the strength of collapse accidents is shown wall and recent wall deposits are required, a load resistance evaluation method of the deposit of the need is the situation. Therefore, in this study, for the evaluation of the evaluation of dry lightweight wall as widely used gypsum board and ALC lightweight wall of two types of laboratory the wall through the previous studies to be installed in direct co-housing to the target and field experiments I want to evaluate the different points.

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Implant-supported overdenture with prefabricated bar attachment system in mandibular edentulous patient

  • Ha, Seung-Ryong;Kim, Sung-Hun;Song, Seung-Il;Hong, Seong-Tae;Kim, Gy-Young
    • The Journal of Advanced Prosthodontics
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    • 제4권4호
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    • pp.254-258
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    • 2012
  • Implant-supported overdenture is a reliable treatment option for the patients with edentulous mandible when they have difficulty in using complete dentures. Several options have been used for implant-supported overdenture attachments. Among these, bar attachment system has greater retention and better maintainability than others. SFI-Bar$^{(R)}$ is prefabricated and can be adjustable at chairside. Therefore, laboratory procedures such as soldering and welding are unnecessary, which leads to fewer errors and lower costs. A 67-year-old female patient presented, complaining of mobility of lower anterior teeth with old denture. She had been wearing complete denture in the maxilla and removable partial denture in the mandible with severe bone loss. After extracting the teeth, two implants were placed in front of mental foramen, and SFI-Bar$^{(R)}$ was connected. A tube bar was seated to two adapters through large ball joints and fixation screws, connecting each implant. The length of the tube bar was adjusted according to inter-implant distance. Then, a female part was attached to the bar beneath the new denture. This clinical report describes two-implant-supported overdenture using the SFI-Bar$^{(R)}$ system in a mandibular edentulous patient.

전국치기공과의 교과과정분석과 전망 (Prospect and Analysis about curriculum of the Department of Dental Laboratory Technology in the whole country)

  • 박용덕;황경숙;김남중
    • 대한치과기공학회지
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    • 제25권1호
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    • pp.203-218
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    • 2003
  • The 3 year graduate school course of the dental technician, which has been enforced since 1994 till the present date, differs from the currently existing 2 year graduate course because of an 8 weeks clinical field training course being newly executed and an imposed curriculum about manufacturing specialized prosthetics like all-ceramic, double prosthetic technology, attachment, and implant. Even though nearly 10 years have passed, the education program of the 18 colleges have still not been standardized and the subjects differing a little, while some are still not following the 3 years graduate course. The goal of this research is to emphasize the qualities of the 3 years graduate program and enable the dental technician to handle clinical models in the dental technical clinic right after graduation by adding clinical field training in the dental technician education program of the 18 colleges. Also in accordance to a national and international increase in esthetical prosthetics, credits, weekly study hours, education practice time of specialized prosthetic dental technology can be analyzed as follows. 1. In the year 2003, currently colleges start clinical practice education starting from the 1st semester of the 2nd year junior year, to the 2nd semester of 3rd year the varying in time with adequate class time, and credits. The average credit is 9.56, and weekly average class time is 18.00 hours. later clinical trainee education will be adjusted to the 3 year graduate school course to 10 credits and 20 hours and the adequate education period should be the 2nd semester of 3rd grade when most basic clinical education has been covered. 2. Currently in the year 2003, all-ceramic education has an average credit of 8.01 in 17 colleges with an exception of Ma-san college. The weekly average theoretical education is 4.94 hours, weekly clinical education of 7.88 hours and currently in 14 colleges porcelain technical class usually starts in the 1st semester of the 2nd year. All-ceramic education is thought to have adequate credits, timing, and weekly study hours. 3. Currently in 2003 implant education is enforced in 11 colleges including Bu-san Catholic university and the education period is usually in the 3rd year. Out of the 11 colleges, only Bu-san Catholic univ., Ma-san and Shinheung college have practice training classes. We knew that Shingu, Dongu, Mokpo science colleges have practice training as a curriculum, namely specific prosthetics laboratory. Out of the 9 colleges enforcing implant education the average credits taken are 2.56, and the average hours of weekly theory education is 2.14, but with the exception of Shinheung college which has an implant practice training course theory and practice classes are not divided. Therefore implant education is thought to start in the 3rd year as a 3 credit course with 3 hours of theory and practice each. 4. Currently in 2003, theoretical attachment education is given in 15 colleges and including practical training it is given in 10 colleges. The education starts 1st semester of the 2nd year till the 2nd semester of the 3rd year. The average credit of attachment theory education in the 15 colleges was 3.64, the average weekly theoretical education was 2.64, and the average weekly practice training out of the schools teaching it was 3.20. Later attachment education is thought to start the 1st semester of the 3rd year as a 3 credit course with 2 hours of theory class and 3 hours of practice training. 5. Double prosthetic technology is currently carried out in Dae-jon Health Science college(2nd year 2nd semester, 2 credits, theory 2hours), Gimcheon college (1 credit, 2 hours of practical training), Bu-san Catholic university (4th year 2nd semester, 4 hours of theory. practice). When the 3 year course is enforced, education will start 1st semester of the 3rd year with 2hours of theory and practice each. 6. The newly installed programs of the 3 year education is clinical field training, and specialized prosthetic manufacturing practice like all-ceramic, double prosthetic technology, attachment, and implant. If such education is to be effectively managed, a primary precursor as systemic basic clinical education is thought to be important. 7. Nationally in the 18 colleges of dental technology the currently executed curriculum course had varying subjects, class time according to the subject, and credits by each college. The curriculum difference between the colleges must be settled.

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Analytical study of the failure mode and pullout capacity of suction anchors in sand

  • Liu, Haixiao;Peng, Jinsong;Zhao, Yanbing
    • Ocean Systems Engineering
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    • 제5권4호
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    • pp.279-299
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    • 2015
  • Suction anchors are widely adopted and play an important role in mooring systems. However, how to reliably predict the failure mode and ultimate pullout capacity of the anchor in sand, especially by an easy-to-use theoretical method, is still a great challenge. Existing methods for predicting the inclined pullout capacity of suction anchors in sand are mainly based on experiments or finite element analysis. In the present work, based on a rational mechanical model for suction anchors and the failure mechanism of the anchor in the seabed, an analytical model is developed which can predict the failure mode and ultimate pullout capacity of suction anchors in sand under inclined loading. Detailed parametric analysis is performed to explore the effects of different parameters on the failure mode and ultimate pullout capacity of the anchor. To examine the present model, the results from experiments and finite element analysis are employed to compare with the theoretical predictions, and a general agreement is obtained. An analytical method that can evaluate the optimal position of the attachment point is also proposed in the present study. The present work demonstrates that the failure mode and pullout capacity of suction anchors in sand can be easily and reasonably predicted by the theoretical model, which might be a useful supplement to the experimental and numerical methods in analyzing the behavior of suction anchors.

In Vitro: Antimicrobial Effect of Lactobacillus salivarius on Staphylococcus pseudintermedius

  • Seo, Haeyoung;Bae, Seulgi;Oh, Taeho
    • 한국임상수의학회지
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    • 제36권2호
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    • pp.98-101
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    • 2019
  • Lactobacillus spp. are the bacteria most commonly used as probiotics and it has been proven that they inhibit pathogenic bacterial growth and improve skin repair in humans. This study was conducted to investigate the growth inhibitory effect of Lactobacillus on Staphylococcus pseudintermedius, the most commonly isolated pathogen in canine pyoderma, and whether Lactobacillus could inhibit the adhesion capability of S. pseudintermedius to canine corneocytes. For this study, L. salivarius and S. pseudintermedius were isolated from healthy beagle fecal samples and the skin surface of dogs with skin infection, respectively. S. pseudintermedius was co-cultured with L. salivarius to assess the inhibitory effect. For the adhesion assay, corneocytes were collected from healthy beagle ventral abdominal skin. Both bacterial species attached to corneocytes and were assessed in number. As a result, L. salivarius significantly inhibited the growth of S. pseudintermedius in the culture medium. Moreover, L. salivarius reduced attachment of S. pseudintermedius in the adhesion assay. These results suggest that L. salivarius has an inhibitory effect on S. pseudintermedius and may be effectively used in the topical therapy of canine skin infections.

CAD/CAM system을 이용한 하악 임플란트 피개의치 수복증례 (The implant overdenture on the edentulous mandible using CAD/CAM system: A case report)

  • 이시은;이소현;전영찬;정창모;윤미정;허중보
    • 대한치과보철학회지
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    • 제53권1호
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    • pp.66-73
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    • 2015
  • 완전, 혹은 부분 무치악 환자의 가철성 보철물 수복치료에서 치아 상실에 따른 치조골 감소와 별형은 의치 사용에 어려움을 준다. 이런 문제를 극복하기 위해 임플란트를 이용하여 가철성 보철물에 지지, 유지, 및 안정을 제공할 수 있다. 임플란트를 이용한 피개의치에 사용되는 어태치먼트는 여러 종류가 있는데, 환자의 여러 조건을 고려하여 어태치먼트를 선택해야 한다. 그 중 milled bar의 경우 임플란트 간 거리가 좁아서 기성 bar를 사용할 수 없는 경우, 또는 기성 bar보다 상부 구조물의 확고한 안정성과 지지를 얻고자 할 때 선택 된다. Milled bar는 cross arch stabilization을 이룰 수 있고, 저작 시 의치의 움직임이 없어 환자에게 편안함을 제공하지만, 숙련된 기공과정을 요한다. 그러나 최근 CAD/CAM의 발전을 통해 milled bar의 제작이 간결해지고 적합성을 증진시킬 수 있었다. 본 증례는 8개의 임플란트가 식립된 하악 완전 무치악의 알츠하이머 환자로 milled bar와 magnet을 이용한 피개의치를 제작하였다. 전신병력이 양호해진 기간 동안 빠른 치료종결이 필요했기 때문에, 통법의 기공 작업을 CAD를 통해 시뮬레이션하여 복잡한 기공과정을 좀더 단순하게 하였고 이로써 치료 기간을 줄일 수 있었다. 이상과 같이 milled bar를 이용한 임플란트 지지 피개의치를 제작하는 과정 중 CAD/CAM system을 적절히 사용하여 심미적, 기능적으로 만족할 만한 결과를 얻었기에 보고하고자 한다.

Passaging Method for Expansion of Undifferentiated Human Embryonic Stem Cells by Pipetting Technique

  • Lee, Sung-Geum;Moon, Sung-Hwan;Lee, Soo-Hong;Lee, Hey-Jin;Kim, Jae-Hwan;Chung, Hyung-Min
    • Reproductive and Developmental Biology
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    • 제30권4호
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    • pp.287-291
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    • 2006
  • We have developed a new passaging technique for the expansion of human embryonic stem cells (hESCs) that involves simply pipetting portions of hESCs acquired from colonies, reducing the laborious and time-consuming steps in the expansion of hESCs. Compared to general mechanical methods of passaging, our pipetting method allowed hESCs colonies to be broken into small fragments, which showed significantly higher attachment rates onto feeder cell layers. This technique produced three times the number of hESCs colonies than conventional mechanical methods. In addition, this pipetting method allowed us to distinguish differentiated hESCs from undifferentiated hESCs during hESCs colony pipetting. The hESCs cultured by pipetting method displayed normal human chromosomes for over 60 passages. According to RT-PCR and immunohistochemical analysis, the hESCs successfully maintained their undifferentiated state and pluripotency which was also confirmed by teratoma formation in viva Therefore, the pipetting method described in this study is a useful tool to efficiently and quickly expand hESCs on a large scale without enzyme treatment.

Structure-Activity Relationship and Evaluation of Phenethylamine and Tryptamine Derivatives for Affinity towards 5-Hydroxytryptamine Type 2A Receptor

  • Shujie, Wang;Anlin, Zhu;Suresh, Paudel;Choon-Gon, Jang;Yong Sup, Lee;Kyeong-Man, Kim
    • Biomolecules & Therapeutics
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    • 제31권2호
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    • pp.176-182
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    • 2023
  • Among 14 subtypes of serotonin receptors (5-HTRs), 5-HT2AR plays important roles in drug addiction and various psychiatric disorders. Agonists for 5-HT2AR have been classified into three structural groups: phenethylamines, tryptamines, and ergolines. In this study, the structure-activity relationship (SAR) of phenethylamine and tryptamine derivatives for binding 5-HT2AR was determined. In addition, functional and regulatory evaluation of selected compounds was conducted for extracellular signal-regulated kinases (ERKs) and receptor endocytosis. SAR studies showed that phenethylamines possessed higher affinity to 5-HT2AR than tryptamines. In phenethylamines, two phenyl groups were attached to the carbon and nitrogen (R3 ) atoms of ethylamine, the backbone of phenethylamines. Alkyl or halogen groups on the phenyl ring attached to the β carbon exerted positive effects on the binding affinity when they were at para positions. Oxygen-containing groups attached to R3 exerted mixed influences depending on the position of their attachment. In tryptamine derivatives, tryptamine group was attached to the β carbon of ethylamine, and ally groups were attached to the nitrogen atom. Oxygen-containing substituents on large ring and alkyl substituents on the small ring of tryptamine groups exerted positive and negative influence on the affinity for 5-HT2AR, respectively. Ally groups attached to the nitrogen atom of ethylamine exerted negative influences. Functional and regulatory activities of the tested compounds correlated with their affinity for 5-HT2AR, suggesting their agonistic nature. In conclusion, this study provides information for designing novel ligands for 5-HT2AR, which can be used to control psychiatric disorders and drug abuse.

Experimental and Theoretical Investigations of PAN Molecular Weight Increase in Precipitation Polymerization as a Function of H2O/DMSO Ratio

  • Zhang, Jing;Bu, Fengjing;Dai, Yongqiang;Xue, Liwei;Xu, Zhixian;Ryu, Seung-Kon;Jin, Riguang
    • Carbon letters
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    • 제11권1호
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    • pp.22-27
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    • 2010
  • The precipitation polymerization of acrylonitrile (AN) was carried out in a mixture solution of dimethyl sulfoxide (DMSO) and water at $50{\sim}65^{\circ}C$ using ${\alpha},{\alpha}'$-azobisisobutyronitrile (AIBN) as an initiator. The increased molecular weight polyacrylonitrile (PAN) was prepared with increasing the $H_2O$/DMSO ratio from 10/90 to 80/20. The viscosity average molecular weight of $H_2O$/DMSO solvent was 4.4 times larger than that of $H_2O$/DMF solvent, and precipitation polymerization was accelerlated due to the far decreased chain transfer effect of DMSO. Based on the experimental results, the increased PAN molecular weight was regarded as the summation of two mechanisms: i) particle-particle aggregation and ii) particle-radical attachment. The theoretical equation derived from the mechanisms was well coincided with the experimental results showing the linear relationship between the viscosity average molecular weight and the H2O/DMSO ratio.

Efficacy of glycine powder air-polishing in supportive periodontal therapy: a systematic review and meta-analysis

  • Zhu, Mengyuan;Zhao, Meilin;Hu, Bo;Wang, Yunji;Li, Yao;Song, Jinlin
    • Journal of Periodontal and Implant Science
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    • 제51권3호
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    • pp.147-162
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    • 2021
  • Purpose: This systematic review and meta-analysis was conducted to assess the effects of glycine powder air-polishing (GPAP) in patients during supportive periodontal therapy (SPT) compared to hand instrumentation and ultrasonic scaling. Methods: The authors searched for randomized clinical trials in 8 electronic databases for relevant studies through November 15, 2019. The eligibility criteria were as follows: population, patients with chronic periodontitis undergoing SPT; intervention and comparison, patients treated by GPAP with a standard/nozzle type jet or mechanical instrumentation; and outcomes, bleeding on probing (BOP), patient discomfort/pain (assessed by a visual analogue scale [VAS]), probing depth (PD), gingival recession (Rec), plaque index (PI), clinical attachment level (CAL), gingival epithelium score, and subgingival bacteria count. After extracting the data and assessing the risk of bias, the authors performed the meta-analysis. Results: In total, 17 studies were included in this study. The difference of means for BOP in patients who received GPAP was lower (difference of means: -8.02%; 95% confidence interval [CI], -12.10% to -3.95%; P<0.00001; I2=10%) than that in patients treated with hand instrumentation. The results of patient discomfort/pain measured by a VAS (difference of means: -1.48, 95% CI, -1.90 to -1.06; P<0.001; I2=83%) indicated that treatment with GPAP might be less painful than ultrasonic scaling. The results of PD, Rec, PI, and CAL showed that GPAP had no advantage over hand instrumentation or ultrasonic scaling. Conclusions: The findings of this study suggest that GPAP may alleviate gingival inflammation more effectively and be less painful than traditional methods, which makes it a promising alternative for dental clinical use. With regards to PD, Rec, PI, and CAL, there was insufficient evidence to support a difference among GPAP, hand instrumentation, and ultrasonic scaling. Higher-quality studies are still needed to assess the effects of GPAP.